1. Field of the Invention
The present invention relates to a contact for use in an electrical connector, especially a contact to connect a chip module with a printed circuit board.
2. Description of the Prior Art
With the development of computer technology, electrical sockets each of which mainly comprises an insulating housing and a plurality of contacts are becoming more and more smaller. On the other hand, the demand of high speed signal transmission results in more and more contacts used in the sockets. So, it will get some problems to arrange so many contacts in such limited area.
U.S. Pat. No. 6,142,792 discloses one conventional electrical socket. The socket comprises a dielectric housing and a plurality of contacts. The housing is formed with a plurality of slots. Each of the contacts comprises a base portion mounted in the slot, a contact portion extending from said base portion but not out of the slot for contacting a solder ball provided on a chip module and a tail portion extending from said base portion in the opposite direction. The contact portion formed with three branches gets a circle in order to contain the solder ball entirely. So it will make reliable electrical contacting between them. However, as the contact portion doesn't extend out of the housing, the solder ball must be configured to enter into the slot and take up huge room. As a result, the pitch of adjacent contacts increases, and the amount of contacts decrease accordingly. Therefore, this type of socket doesn't meet the needs of high speed signal transmission.
Hence, a type of improved contact for use in an electrical socket is required to overcome the disadvantage of the prior art.